Electronic devices, and particularly portable electronic devices such as mobile phones, tablet computers, laptop computers and the like, typically rely on battery power. For a variety of reasons relating to various design considerations, the DC voltage available from the battery may not match the voltage required to power the various internal components. Thus, one or more power conversion circuits a/k/a DC-DC converters may be employed.
When an electronic component requires a higher voltage than that supplied by the battery, a boost converter may be employed. Alternatively, when an electronic component requires a lower voltage than that supplied by the battery, a buck converter may be employed. More sophisticated converter designs, such as buck-boost converters, flyback converters, Cuk converters, and the like are also known to those skilled in the art.
Whatever type of converter is used, the voltage output of the converter may not be sufficiently stable for the particular electronic device being powered. In such cases, a voltage regulator may be used. Linear voltage regulators are quite common, but suffer from a disadvantage due to their inherent efficiency. Additionally, the regulator may be integrated with the power converter itself. For example, in some cases, a buck converter may be used as a voltage regulator that operates substantially more efficiently than a conventional linear regulator.
One issue that has presented itself with respect to such circuits is the response time of the circuit to changes in the load and the deleterious effect this can have on the output voltage. For example, a substantial increase in the load on the circuit, such as that caused by a device switching on or coming out of a power saving mode, may cause a decrease in output voltage below a desired value. Alternatively, a substantial decrease in the load on the circuit, such as that caused by a device switching off or entering a power saving mode, may cause an increase in output voltage above a desired value. In either case, proper and/or reliable operation of the load may be compromised by these voltage transients. Thus, improved circuits and techniques for dealing with such load transients are desirable.